Influence of silver doping on the photocatalytic activity of titania films

• Published in: Applied surface science Vol. 200; no. 1; pp. 239 - 247
• Main Authors: He, Chao, Yu, Yun, Hu, Xingfang, Larbot, André
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 15.11.2002; Elsevier Science
• Subjects: Catalysis; Catalysts: preparations and properties; Chemistry; Doping; Exact sciences and technology; General and physical chemistry; Photocatalytic activity; Photochemistry; Physical chemistry of induced reactions (with radiations, particles and ultrasonics); Sol–gel process; Structure; Theory of reactions, general kinetics. Catalysis. Nomenclature, chemical documentation, computer chemistry; TiO 2; Photocatalytic activity; Sol–gel process; TiO 2; Structure; Doping; BET method; Sol gel process; Photocatalysis; Silver addition; Microstructure; Titanium oxide; Catalyst activity; Thin film
• ISSN: 0169-4332; 1873-5584
• DOI: 10.1016/S0169-4332(02)00927-3

By means of X-ray diffraction, BET nitrogen adsorption, UV-Vis-NIR transmission spectroscopy, transmission electron microscope, scanning electron microscope, X-ray photoelectron spectroscopy and photodegradation of methylene blue, effects of Ag doping on the microstructure and photocatalytic activity of TiO 2 films prepared by sol–gel method were studied. It is found that with a suitable amount (2–4 mol%), the Ag dopant increases the photocatalytic activity of TiO 2 films. The mechanism can be attributed to that (1) anatase grain sizes decrease with Ag doping and the specific surface areas of doped TiO 2 films increase, the charge transfer in TiO 2 films is promoted; (2) by enhancing the electron–hole pairs separation and inhibiting their recombination, the Ag dopant enhances the charge pair separation efficiency for doped TiO 2 films.